The present invention relates to a device for a motorized saw of the kind wherein the saw is built up from a reciprocating toothed saw blade and a relative to this stationary support plate.
Electrically driven saws with a reciprocating saw blade motion are long known especially for jig sawing in thin materials such as plywood, fibre board, particle board etc. In these applications narrow saw blades are often used whose width seldom exceed a tenth of the length and therefore sawing of curved contours is facilitated and the friction between the blade and the work piece is diminished. These constructions, however, have the disadvantage of small flexural rigidity and therefore it will be difficult to saw straight in thicker materials and they have been used mainly in materials having a thickness over 3 cm for works with small demands on accuracy, for example demolishing and ingot building.
Furthermore it is known to make motorized saws wherein the saw teeth are arranged on a narrow reciprocating blade, which is movable along the edge of a stationary broad support plate. These are used for example for cutting frozen carcasses, and earlier also for wood felling. In those two applications there has been required motors of considerable power in order to overcome the friction against the support plate as well as the cutting force. There exists a desire to be able to use a corresponding construction for small hand-held saws in order to be able to saw straight cuts in thick wood.
An object of the present invention is to provide a device for such saws arranged such that the friction can be diminished and therefore a power-requiring motor can be used which has a small weight.